1. Field of the Invention
The instant disclosure relates to an antenna; in particular, to a near field magnetic coupling antenna and a RFID (Radio Frequency Identification) reader having the same near field magnetic coupling antenna.
2. Description of Related Art
Radio frequency identification is a wireless communication technology which utilizes a reader and a tag to constitute a RFID system. The RFID reader transmits radio waves, and the RFID tag generates electric current according to electromagnetic induction of the radio waves. The generated electric current is for the operation of the chip (or integrated circuit) in the RFID tag and the RFID tag transmits electromagnetic wave responding to the RFID reader.
The operation bands of existing RFID technology is usually the ultra high frequency (UHF) band. The UHF band which is widely used in wireless communications ranges from 300 MHz to 3 GHz. The RFID technology utilizing the UHF band enables the RFID reader to identify a RFID tag located within 10 centimeter from the RFID reader.
The antenna of the traditional RFID reader is usually a loop antenna. The loop antenna is simpler in structure and smaller in volume, with the manufacturing cost of the loop antenna relatively low. However, the magnetic field generated by the traditional loop antenna is not so uniform. And because of the loop structure of the traditional loop antenna the magnitude of the electromagnetic field (or magnetic field) may be insufficient.